Constriction valve

ABSTRACT

Constriction valves for catheters and method of using constriction valves are presented. The catheter valve has a conduit comprising mesh defining a lumen. The catheter also has a biasing member that is configured to bias the lumen from an open position to a closed position by altering an effective length of the conduit or altering the circumference of the conduit. The biasing member is further configured to change its configuration by changes of intraluminal pressure of the valve. A user can insert a tool into a catheter having a valve by manipulating the valve to expand a substantially closed lumen by compressing the biasing member, twisting the biasing member, or pulling on a cord coupled with the valve.

This application is a divisional application of U.S. Pat. No.10,183,159, filed Apr. 18, 2018, which claims the benefit of andpriority to U.S. Provisional Patent Application No. 62/267,777, filedDec. 15, 2015, each of which are incorporated herein in their entiretyby reference.

FIELD OF THE INVENTION

The field of the invention is a constriction valve for a catheter.

BACKGROUND

The background description includes information that may be useful inunderstanding the present invention. It is not an admission that any ofthe information provided herein is prior art or relevant to thepresently claimed invention, or that any publication specifically orimplicitly referenced is prior art.

Cardiac catheterization is a procedure to insert catheters into theheart via an artery or vein to diagnose or treat certain cardiovascularconditions. During cardiac catheterization, a catheter is inserted in anartery or vein in patient's neck, groin or arm. While a radial artery isoften used as an access point to the heart during cardiaccatheterization, a femoral artery is preferred because it has largerdiameter, which allows the insertion of catheters in larger sizes. Oncea catheter is properly inserted and positioned, various procedures canbe performed by inserting devices into the lumen of the catheter. Forexample, coronary angiography can be performed by inserting aradio-dense tube to visualize the vasculature structures in the heart.In another example, balloon septostomy can be performed by inserting aballoon catheter to increase the blood flow in a septum of the heart.

Most common complications of cardiac catheterization include bleeding,thrombosis, and vascular trauma. These complications are especiallyproblematic when the sheath of the catheter is relatively large (e.g.,more than 8F), because arterial blood pressure at the site of theinsertion is often more than 50 mmHg. Thus, blood spurting from thefemoral artery can frequently occur when tubes are disoriented ordissociated from the catheter, or when a health provider replaces aninserted device. While manual compression has been most commonly used toreduce the complication, it requires a significant amount of pressureover the artery, which may cause pain for some patients, and deep veinthrombosis due to femoral artery compression and stasis.

Many technologies have been developed to prevent blood spurting withoutrequiring manual compression over the patient's body. For example, U.S.Pat. No. 5,582,165 to Bryan discloses a catheter connector which issimilar to Chinese finger trap. The catheter connector is configured tocontract in diameter when the adaptor is pulled or stretched in an axialdirection. This reduces blood spurting if the catheter is pulled orslipped out by inadvertent jerking of therapist or patient. U.S. Patentapplication No. 2004/0012235 to Pinchuk discloses a stretch-valve tubethat applies a similar Chinese finger trap mechanism. In Pinchuk, whenthe flexible valve tube is stretched (e.g., when a urinary catheter isprematurely pulled out), the stretched portion collapses inwardlytowards the longitudinal axis as the catheter body lengthens.

Others have sought to solve the problem by mechanically pressing in upona portion of the catheter. For example, U.S. Pat. No. 7,914,492 toHeuser discloses a catheter introducer system where a portion of thecatheter can be shut using a closing system similar to a camera shuttermechanism. In Heuser, a shutter positioned radially about a cathetershutter can be opened by inserting an opening device (e.g., a tip ofneedle) through the lumen of the catheter, shutter, and then closedautomatically when the needle (or other opening device) is removed fromthe catheter.

All publications identified herein are incorporated by reference to thesame extent as if each individual publication or patent application werespecifically and individually indicated to be incorporated by reference.Where a definition or use of a term in an incorporated reference isinconsistent or contrary to the definition of that term provided herein,the definition of that term provided herein applies and the definitionof that term in the reference does not apply.

Thus, there is still a need for improved constriction valve systems forcatheters.

SUMMARY OF THE INVENTION

The inventive subject matter provides systems, devices for aconstriction valve for a catheter that can be used for cardiaccatheterization, urinary catheterization or any other catheterization ofthe body area, especially those with high fluid pressures, and methodsof using the constriction valve.

One aspect of the invention includes a catheter valve having a conduitwhich defines a lumen. The catheter valve can also include a spring thatis configured to bias the lumen from an open position to a closedposition by altering an effective length of the conduit by at least 1mm.

Another aspect of the invention includes a catheter for insertion into avascular structure. The catheter includes an elongated body, which has aproximal end and a distal end. The catheter further includes a valvepositioned at the distal end of the elongated body. It is especiallypreferred that the valve includes a conduit defining a lumen, and aspring that is configured to bias the lumen from an open position to aclosed position by altering an effective length of the conduit by atleast 1 mm.

Another aspect of the invention includes a method of inserting a toolinto a catheter, where the catheter has a valve with first and secondfinger contacts, and the method includes manipulating the valve toexpand a substantially closed lumen. The step of manipulation can beachieved in any one or more of several different motions, by (a) movingthe first contact towards the second contact, (b) twisting the firstcontact relative to the second contact, and (c) pulling on a cord.

Another aspect of the invention includes a catheter valve having aconduit that defines a lumen. The catheter valve includes a spring thatis configured to bias the lumen from an open position to a closedposition, by decreasing a circumference of at least a portion of theconduit by at least 1 mm.

Various objects, features, aspects and advantages of the inventivesubject matter will become more apparent from the following detaileddescription of preferred embodiments, along with the accompanyingdrawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a perspective view of one embodiment of catheterconstriction valve in a closed configuration.

FIG. 1B illustrates a perspective view of the catheter constrictionvalve of FIG. 1A in an open configuration.

FIG. 2A illustrates a perspective view of another embodiment of catheterconstriction valve in a closed configuration.

FIG. 2B illustrates a perspective view of the catheter constrictionvalve of FIG. 2A in an open configuration.

FIG. 3A illustrates a perspective view of another embodiment of catheterconstriction valve in a closed configuration.

FIG. 3B illustrates a perspective view of the catheter constrictionvalve of FIG. 3A in an open configuration.

FIG. 4 illustrates a perspective view of another embodiment of catheterconstriction valve in an open configuration.

FIG. 5A illustrates a perspective view of the constriction valve of FIG.4, in a closed configuration.

FIG. 5B illustrates a cross-section of a constriction portion theconstriction valve of FIG. 5, depicting compression of an optional fluidbag around the conduit.

FIG. 6 illustrates a perspective view of another embodiment of catheterconstriction valve housed in a catheter.

FIG. 7 illustrates a perspective view of another embodiment of catheterconstriction valve.

FIG. 8A illustrates a perspective view of another embodiment of catheterconstriction valve housed in a catheter in an open configuration.

FIG. 8B illustrates a perspective view of the catheter constrictionvalve of FIG. 8A in a closed configuration.

DETAILED DESCRIPTION

The inventive subject matter provides a constriction valve, especiallyfor use in cardiac catheterization, urinary catheterization or any othercatheterization to the body area with a high fluid pressure. Further,the inventive subject matter includes catheters that include theinventive constriction valves and methods of using such valves andcatheters.

While the inventive subject matter is susceptible of variousmodification and alternative embodiments, certain illustratedembodiments thereof are shown in the drawings and will be describedbelow in detail. It should be understood, however, that there is nointention to limit the invention to the specific form disclosed, but onthe contrary, the invention is to cover all modifications, alternativeembodiments, and equivalents falling within the scope of the claims.

The following discussion provides many example embodiments of theinventive subject matter. Although each embodiment represents a singlecombination of inventive elements, the inventive subject matter isconsidered to include all possible combinations of the disclosedelements. Thus if one embodiment comprises elements A, B, and C, and asecond embodiment comprises elements B and D, then the inventive subjectmatter is also considered to include other remaining combinations of A,B, C, or D, even if not explicitly disclosed.

In some embodiments, the numbers expressing quantities or ranges, usedto describe and claim certain embodiments of the invention are to beunderstood as being modified in some instances by the term “about.”Accordingly, in some embodiments, the numerical parameters set forth inthe written description and attached claims are approximations that canvary depending upon the desired properties sought to be obtained by aparticular embodiment. In some embodiments, the numerical parametersshould be construed in light of the number of reported significantdigits and by applying ordinary rounding techniques. Notwithstandingthat the numerical ranges and parameters setting forth the broad scopeof some embodiments of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspracticable. The numerical values presented in some embodiments of theinvention may contain certain errors necessarily resulting from thestandard deviation found in their respective testing measurements.Unless the context dictates the contrary, all ranges set forth hereinshould be interpreted as being inclusive of their endpoints andopen-ended ranges should be interpreted to include only commerciallypractical values. Similarly, all lists of values should be considered asinclusive of intermediate values unless the context indicates thecontrary.

As used in the description herein and throughout the claims that follow,the meaning of “a,” “an,” and “the” includes plural reference unless thecontext clearly dictates otherwise. Also, as used in the descriptionherein, the meaning of “in” includes “in” and “on” unless the contextclearly dictates otherwise.

All methods described herein can be performed in any suitable orderunless otherwise indicated herein or otherwise clearly contradicted bycontext. The use of any and all examples, or exemplary language (e.g.,“such as”) provided with respect to certain embodiments herein isintended merely to better illuminate the invention and does not pose alimitation on the scope of the invention otherwise claimed. No languagein the specification should be construed as indicating any non-claimedelement essential to the practice of the invention.

Groupings of alternative elements or embodiments of the inventiondisclosed herein are not to be construed as limitations. Each groupmember can be referred to and claimed individually or in any combinationwith other members of the group or other elements found herein. One ormore members of a group can be included in, or deleted from, a group forreasons of convenience and/or patentability. When any such inclusion ordeletion occurs, the specification is herein deemed to contain the groupas modified, thus fulfilling the written description of all Markushgroups used in the appended claims.

One aspect of the inventive subject matter includes a catheter valve.The catheter valve includes a conduit, which defines a lumen of thecatheter, and a spring around the conduit. The spring is configured tobias the lumen from an open position to a closed position by altering aneffective length of the conduit. In a preferred embodiment, the changein effective length of the conduit needed to reconfigure the lumen froman open position to a closed position is at least 10 mm, preferably atleast 5 mm, and most preferably at least 1 mm.

As used herein, a lumen is an inside space of a structure. In someembodiments, the shape of the lumen depends on the shape of the conduit.For example, the conduit can a tubular shape, a twisted tubular shape, acuboid shape, or a triangular prism shape, and the shape of the lumencan be shaped to match the conduit. In other embodiments, the shape ofthe lumen can be independent from the shape of the conduit. For example,where a conduit has tubular shape, the lumen could have a cuboid shape,or vice versa.

As used herein, the term “closed” with respect to a portion of a lumenmeans that the cross-sectional flow area of the portion is reduced by atleast 20% at the then-current pressure, temperature and otherconditions, relative to a fully open position at the same conditions.

As used herein, a spring can include any resilient device that can bepressed and pulled. Any suitable types of springs (e.g., mechanicalsprings, hydraulic springs, pneumatic springs, etc) that can be to exerttension or absorb movement of the conduit are contemplated. For example,contemplated springs includes helical springs (e.g., a coil spring, acompression spring, an extension spring, a torsion spring, etc), leafsprings, wave springs, hydraulic springs operated by fluids (e.g., gas,liquid, etc.), pneumatic springs filled with compressed air or othertypes of gas.

Thus, depending on the type of spring used, and the shape and of thevalve, a spring is configured to bias the lumen from an open position toa closed position by increasing the effective length of the conduit(e.g., by at least 10 mm, 5 mm, 1 mm, etc.), or by decreasing theeffective length of the conduit (e.g., by at least 10 mm, 5 mm, 1 mm,etc.). For example, if the spring is a compression spring and theconduit is configured to be closed when it is stretched, the spring isconfigured to bias the lumen from the open position to the closedposition. For another example, if the spring is an extension spring andthe conduit is configured to be closed when it is compressed, the springis configured to bias the lumen from the close position to the openposition.

FIGS. 1A-B illustrate one embodiment of the constriction valve 100 for acatheter in an at last partially closed configuration (FIG. 1A) and inan open configuration (FIG. 1B). The constriction valve 100 includes anelongated conduit 115 having a proximal end 105 and a distal end 110.The constriction valve 100 further includes helical coil spring 120coupled with (e.g., wrapped around) the surface of the conduit 115.

In this embodiment, it is contemplated that any suitable types ofmaterials or structures can be used to increase or decrease the valve'slength upon the force or pressure exerted by the spring. Preferably, theconduit 115 comprises a mesh (e.g., extruded, oriented, expanded, woven,tubular, knitted, welded, photochemically etched, electroformed, etc.).The mesh can also be made from any suitable type of material(s). Forexample, the mesh can be made of any or more of plastic materials (e.g.,polypropylene, polyethylene, nylon, PVC or PTFE), metal materials (e.g.,aluminum, copper, platinum, metal alloys, etc.), or fiber (e.g., cotton,synthetic fiber, glass fiber, etc.).

It is preferred that at least a portion of the mesh is elastomeric, suchthat compression or expansion of the elastic portion of the mesh candecrease or increase the length of the conduit. However, it is alsocontemplated that in some embodiments, the mesh is not elastomeric. Inthese non-elastomeric embodiments, the mesh comprises a network of wiresand/or threads, which are coupled together at contact points about whichcoupled components can pivot, rotate, turn, swivel, revolve or spin,such that the length of the conduit can increase or decrease by thecollective movements of the contact points.

In the embodiment shown in FIGS. 1A-B, it is generally preferred thatthe spring 120 is a compression helical spring, which shortens itslength upon an axial force pressing against ends of the spring. Thus,when no axial force is exerted on the spring, the spring is configuredto be in its extended configuration, which increases the length of aconstricting portion of the conduit 115. Increase of the conduit lengthstretches the surface of the conduit, which in turn decreases thediameter of the lumen of the conduit, and biases the conduit from an atleast partially open configuration to a more closed configuration.However, in some other embodiments, it is contemplated that the spring120 is an extension helical spring, which stretches upon action of anaxial tensioning force. Thus, when no axial force is exerted on thespring, the spring is configured to be in its compressed configuration,which decreases the length of a constricting portion of the conduit 115.Decrease of the conduit length increases the diameter of the lumen ofthe conduit, which in turn, biases the conduit from an at leastpartially closed configuration to a more open configuration.

Further, in the embodiment shown in FIGS. 1A-B, it is contemplated thatthe spring 120 has a tension or compression strength such that theconduit 115 is in the closed position below an intraluminal pressure of15 mmHg, preferably below 10 mmHg, and more preferably below 5 mmHg. Itis also contemplated that the spring 120 has a tension or compressionstrength such that the conduit 115 is in the open position above anintraluminal pressure of 15 mmHg, preferably above at least 20 mmHg, andmore preferably above at least 25 mmHg. In most cases, insertion of adevice (e.g., a needle, a tube, a stent, etc.) into the lumen of theclosed conduit will increase the intraluminal pressure above 15 mmHg,and would therefore change the conduit from a closed configuration to anopen configuration. Presumably, removal of the device from the lumen ofthe open conduit would then reduce the intraluminal pressure below 15mmHg, and would therefore change the conduit from an open configurationto a closed configuration.

FIG. 1A-B should be contemplated to include a valve that is biased onlypartially closed, providing a relatively narrow opening that allows forrelatively slow passage of the passing fluid. For example, a cathetercould have a constriction portion with a sufficiently narrow openingsuch that blood flowing through the opening under a pressure of 50 mmHgcan flow, but at a desirably slow rate. The constriction portion canstill comprise a mesh having sufficiently flexibility to accommodate aninserted tool of relatively large cross-section.

In FIGS. 2A-B constriction valve 200 generally includes an elongatedconduit 215 having a proximal finger contact 205, a distal fingercontact 210, and helical coil spring 220 coupled with (e.g., wrappedaround) the surface of the conduit 215. FIG. 2A shows the constrictionvalve 200 in an at last partially closed configuration, and FIG. 2Bshows the constriction valve 200 in an open configuration.

In this embodiment, the constriction valve 200 further includes a cord250 that is coupled with the coil spring 220. In this particularembodiment, cord 250 has two ends 250A, 250B, and is tied to the distalfinger contact 210 at 252. Pulling on either or both of the two ends250A, 250B moves the proximal distal and finger contacts 205, 210towards each other. Cord 250 can be coupled to distal finger contact 210in any suitable manner, including for example, bonding, welding, andsuturing. Pulling on either or both of the two ends 250A, 250B willdecrease the length of the conduit 215, and thereby changes the conduit215 from a closed configuration to an open configuration.

In FIGS. 2A-B, the cord 250 is wrapped around or weaved into the surfaceof the conduit 215. In other embodiments, the cord 250 can be placedwithin the lumen of the conduit 215. In still other embodiments, it iscontemplated that the cord 250 can be attached to the coil spring 220,having minimal contact with the surface of the conduit 215.

In FIGS. 3A-B an alternative constriction valve 300 again includes anelongated conduit 315 having a proximal finger contact 305 (proximalend) and a distal finger contact 310 (distal end), and does not show,but should be interpreted to include, a helical coil spring coupled withthe surface of the conduit 315, and a cord coupled with the surface ofthe conduit 315. FIG. 3A shows the constriction valve 300 in an at lastpartially closed configuration, and FIG. 3B shows the constriction valve300 in an open configuration.

In this embodiment, however, the constriction valve 300 further includesa finger holder 335 that is coupled with the cord 350. The finger holder335 is depicted as a ring, but should be interpreted generically toinclude a hook, or in any suitable shape that can be used to facilitatetransfer of a pulling force against the cord 350. The finger holder 335can comprise any suitable type of material or materials. For example,the finger holder 335 can be made of plastic materials (e.g.,polypropylene, polyethylene, nylon, PVC or PTFE), metal materials (e.g.,aluminum, copper, platinum, metal alloys, etc.), or fiber (e.g., cotton,synthetic fiber, glass fiber, etc.).

Pulling of the finger holder 335 pulls the distal finger contact 310toward the proximal finger contact 305. Unless the force is evenlydistributed along circumference of the conduit 315, the conduit 315 willexperience a bending force. To prevent bending of the conduit 315,constriction valve 300 further includes an anti-bending mechanism 330.In FIG. 3 the anti-bending mechanism 330 comprises a telescopingstructure having a plurality of telescoping members. At least onetelescoping member is attached to each of the proximal finger contact305 (proximal end) or the distal finger contact 310 (distal end). Allother suitable anti-bending mechanisms are contemplated, including forexample, two opposite-facing curved elements (not shown). In thatembodiment, each curved element could have a proximal end and a distalend, with the proximal end coupled (e.g., affixed, attached, etc) to theproximal finger contact 305 (proximal end), and the distal end iscoupled (e.g., affixed, attached, etc) to the distal finger contact 305(distal end).

Other contemplated catheter valves operate without necessarily incurringa change in length of the conduit. For example, either the conduit, oneor more members about the conduit, or some combination of both can betwisted in a manner that alters a circumference of at least a portion ofthe conduit. In a preferred embodiment, the effective circumference ofthe conduit changed to bias the lumen from an open position to a closedposition is at least 10 mm, preferably 5 mm, and most preferably 1 mm.

In a manner similar to that described above, it is contemplated thatconstricted portions of twisting embodiments can be closed below anintraluminal pressure of 15 mmHg, preferably below 10 mmHg, and morepreferably below 5 mmHg, and opened above an intraluminal pressure of atleast 15 mmHg, preferably above at least 20 mmHg, and more preferablyabove at least 25 mmHg. Increase in intraluminal pressure can, ofcourse, be effected by inserting a device (e.g., a needle, a tube, astent, etc.) of sufficient cross-sectional area into the lumen of theclosed conduit.

In FIG. 4 a constriction valve 400 includes an elongated conduit 415having a proximal finger contact 405 and a distal finger contact 410. Inthis embodiment, the constriction valve 400 further includes a spring420 having a plurality of fingers that curvatively disposed around theconduit (e.g., helical torsion spring, etc.). As used herein, a fingerof the spring 420 refers a single coil or thread that stretches from theproximal finger contact 405 to the distal finger contact 410. Thecurvature of the fingers from proximal finger contact 405 to distalfinger contact 410 is at least 1 degree, preferably at least 10 degrees,and more preferably at least 20 degrees. FIG. 4 illustrates theconstriction valve 400 in an open configuration.

FIG. 5A illustrates the constriction valve 400 in a closedconfiguration. In this configuration, it is contemplated that the spring420 is twisted by relative rotational movements of the proximal fingercontact 405 and the distal finger contact 410 (e.g., clockwise for theproximal finger contact and counterclockwise for the distal fingercontact). Such twisting exerts pressure onto the surface of the conduit415, especially more pressure toward the center of the conduit (e.g.,middle section between the proximal finger contact 405 and the distalfinger contact). Constriction that results from twisting will likelycause a gradual narrower towards the center of the conduit 415, so thatthe circumference of the lumen at the region of greatest constrictioncan be less than 20% (and more preferably less than 10%) of thecircumference of the lumen at one of the proximal finger or distalfinger contacts 405, 410.

In some embodiments, where the conduit 415 comprises a resilientmaterial (e.g., rubber, fibers, etc.), exerting gradual pressure overthe surface of the conduit 415 can effectively decrease thecircumference of at least a portion of the conduit 415, and therebychange the conduit from the open configuration to the closedconfiguration. Thus, in turn, releasing the pressure from the surface ofthe conduit 415 by untwisting the spring 420 can effectively increasethe circumference of the conduit 415 back to the original circumferenceof the conduit, and thereby change the conduit from the closedconfiguration to the open configuration.

FIG. 5B shows a cross section of FIG. 5A along the dotted line. In FIG.5B, an optional fluid bag 440 is disposed around the conduit 415, andpushing inwardly on conduit 415 under force of the spring 420, asdepicted by arrows 445. Fluid bag 440 can comprise plastic, rubber, orany other suitably resilient material(s), and can contain a pressurizedgas, liquid, gel, or any other suitable fluid.

In FIG. 6 constriction valve 500 again includes an elongated conduit 515having a proximal finger contact 505 and a distal finger contact 510,but here includes a spring 520 having a plurality of leaves (e.g. 520A,520B, 520C) that are curvatively disposed around the conduit.

Preferably, each leaf of the spring 520 comprises a curved diaphragmhaving a proximal end and a distal end. At least a portion of theproximal end of the leaf is attached (e.g., affixed, etc) to at least aportion of the proximal finger contact 505, and at least a portion ofthe distal end of the leaf is attached (e.g., affixed, etc) to at leasta portion of the distal finger contact 510.

In a preferred embodiment, the spring 520 comprises a resilient orelastomeric material such that the spring 520 is twisted by relativerotational movements of the proximal finger contact 505 and the distalfinger contact 510 (e.g., clockwise for the proximal finger contact andcounterclockwise for the distal finger contact). Such twisting exertspressure onto the surface of the conduit 515, especially more pressuretoward the center of the conduit (e.g., middle section between theproximal finger contact 505 and the distal finger contact). Constrictionthat results from twisting will likely cause a gradual narrower towardsthe center of the conduit 515, so that the circumference of the lumen atthe region of greatest constriction can be less than 20% (and morepreferably less than 10%) of the circumference of the lumen at one ofthe proximal finger or distal finger contacts 505, 510. The constrictingmechanism of FIG. 6 is thus similar to that of FIG. 5, with a majorexception that the constricting mechanism of FIG. 6 operates more like acamera shutter.

Another aspect of the invention includes a catheter that includes any ofthe inventive valves. Contemplated catheters include an elongated bodyhaving a proximal end and a distal end, and a valve positioned at thedistal end of the elongated body. As used herein, the proximal endrefers to an end close to the user (e.g., a medical provider, atechnician, etc.) and the distal end refers to an end close to thepatient.

The elongated body can be in various shapes (e.g., a tube shape, acuboid shape, a triangular prism shape, etc.). In a preferredembodiment, the elongated body comprises at least a partiallyelastomeric material (e.g., a rubber, a plastic, etc.). However, it isalso contemplated that the elongated body comprises non-elastomericmaterials (e.g., metal, etc).

In some embodiments, the catheter includes a main catheter branch andone or more side catheter branches at its distal end. The side branchescan branch out at one or more multifurcation points. Preferably, theconstriction valve is located in the main branch of the catheter so thatit can constrict the backflow of the fluid from the body upon removal ofthe devices inserted into the catheter. The distal end of the valve canbe positioned at any suitable distance from the first multifurcationpoint, preferably at least within 5 cm, more preferably within 3 cm, andmost preferably within 1 cm.

In FIG. 7 catheter 600 again includes an elongated body 635 and aconstriction valve 602 located inside the elongated body 635, anelongated conduit 615 having a proximal finger contact 605 and a distalfinger contact 610. In this embodiment, the constriction valve 602further includes a spring 650 having a plurality of fingers thatcurvatively disposed around the conduit 615 (e.g., helical torsionspring, etc.).

The constricting mechanism of FIG. 7 is similar to that of FIGS. 5 and 6with a major exception that the constriction valve 602 includes ahelical coil spring 650 coupled with (e.g., wrapped around) the surfaceof the conduit 615. By having two different types of springs, theconstriction valve can be closed either by pulling the distal end 610 ofthe valve 602 closer to the proximal end 605 of the valve 602, or bytwisting the distal end 610 of the valve 602 relative to the proximalend 605 of the valve.

FIGS. 8A-B illustrate a catheter 700. FIG. 8A shows a catheter 700 witha constriction valve 702 in an open configuration, and FIG. 8B shows thesame catheter 700 with constriction valve 702 in an at least partiallyclosed configuration. The catheter 700 includes an elongated body 735and a constriction valve 702 located inside the elongated body 735. Theconstriction valve 702 includes an elongated conduit 715 having aproximal finger contact 705 and a distal finger contact 710, and aspring 720 having a plurality of fingers that curvatively disposedaround the conduit 715 (e.g., helical torsion spring, etc.).

In this embodiment, the catheter includes a controller 760 coupled withat least a portion of the proximal end 705 via an elongated opening 755on the elongated body 735 of the catheter 700. The controller 760 isdepicted as a stick handle, but should be interpreted generically toinclude a handle, a button, or in any suitable shape that can be used tofacilitate transfer of a rotating force against the proximal end 705.The proximal end 705 of the valve can be rotated as the controller 760is moved along the elongated opening 755. When the proximal end 705 isrotated relative to the distal end 710 of the valve, the spring 720coupled to the proximal end 705 and the distal end 710 is twisted suchthat the twisted springs 720 exerts pressure onto the surface of theconduit 715. Thus, the constricting mechanism of FIG. 8 is similar tothat of FIGS. 5, 6, and 7.

Another aspect of the invention includes a method of inserting a toolinto a catheter having a constriction valve having proximal and distalfinger contacts described one of FIGS. 1-8. In a preferred method, auser inserts a tool into a catheter by manipulating a valve to expand asubstantially closed lumen to change the valve from a closedconfiguration to an open configuration. In one embodiment, the user canmanipulate the valve by moving one of the proximal and distal fingercontacts towards with each other. In another embodiment, the user canmanipulate the valve by twisting or rotating the one of the proximal anddistal finger contacts relative to another. Still in another embodiment,the user can manipulate the valve by pulling on a cord, which is coupledto at least one of the proximal and distal finger contacts of the valve.

In a case where the intraluminal pressure generated by inserting a toolis less than a threshold pressure for the spring to be expanded orcompressed (or twisted), the valve can be manipulated to change thevalve into an open configuration prior to inserting the tool into thelumen of the valve. However, in a case where the intraluminal pressuregenerated by inserting a tool is more than a threshold pressure for thespring to be expanded or compressed (or twisted), the manipulating stepis performed following partial insertion of the tool into a lumen of thevalve.

Manipulation of the valve can be performed in various ways. For example,it is contemplated that a user can directly pull, push, twist, or rotatea portion of the valve using the user's finger pressure to operate thevalve against the force (e.g., tension) of a spring. However, it is alsocontemplated that a user can operate an electronic system (e.g., bypushing a button, touching a screen, etc.) that is configured to operatethe movement of a spring of the valve.

It should be apparent to those skilled in the art that many moremodifications besides those already described are possible withoutdeparting from the inventive concepts herein. The inventive subjectmatter, therefore, is not to be restricted except in the spirit of theappended claims. Moreover, in interpreting both the specification andthe claims, all terms should be interpreted in the broadest possiblemanner consistent with the context. In particular, the terms “comprises”and “comprising” should be interpreted as referring to elements,components, or steps in a non-exclusive manner, indicating that thereferenced elements, components, or steps may be present, or utilized,or combined with other elements, components, or steps that are notexpressly referenced. Where the specification claims refers to at leastone of something selected from the group consisting of A, B, C . . . andN, the text should be interpreted as requiring only one element from thegroup, not A plus N, or B plus N, etc.

What is claimed is:
 1. A catheter valve, comprising: a conduit having aproximal end and a distal end, wherein the conduit defines a lumen, andfurther wherein the conduit comprises a mesh having at least a portionthat is elastomeric; a biasing member disposed between the proximal endand the distal end of the conduit; wherein the biasing member comprises(1) an extended configuration in which the biasing member is configuredto stretch the conduit outwardly along an axis to thereby cause thelumen to decrease to a first diameter and partially close the conduit,and (2) a compressed configuration above a first intraluminal pressurein which the biasing member is compressed to thereby allow the conduitto collapse inwardly along the axis and cause the lumen to increase fromthe first diameter to a second diameter to open the conduit.
 2. Thevalve of claim 1, wherein the biasing member is configured to bias theconduit from an open position to a partially closed position bystretching the conduit and thereby increasing the effective length ofthe conduit by at least 1 mm.
 3. The valve of claim 1, wherein the firstintraluminal pressure is 25 mmHg.
 4. The valve of claim 1, wherein thebiasing member is configured to bias the lumen to a partially closedposition solely by stretching the conduit along the axis to therebycause the lumen to decrease to the first diameter.
 5. The valve of claim1, wherein the biasing member is in the extended configuration below asecond intraluminal pressure of 10 mmHg.
 6. The valve of claim 1,wherein the biasing member is coupled with a cord wrapped around atleast a portion of the conduit, and configured such that pulling on thecord opens the conduit.
 7. The valve of claim 1, further comprising afirst and second finger contacts, and a cord mechanically coupled to thefirst finger contact such that pulling on the cord moves the firstfinger contact towards the second finger contact.
 8. The valve of claim7, further comprising a finger holder coupled to the cord such thatpulling on the finger holder moves the first finger contact towards thesecond finger contact.
 9. The valve of claim 1, further comprising ananti-bending mechanism disposed along the conduit.
 10. The valve ofclaim 9, wherein the anti-bending mechanism comprises a plurality oftelescoping members.
 11. The valve of claim 1, wherein the firstdiameter is at least 20% smaller than the second diameter.
 12. The valveof claim 1, wherein the biasing member is configured to transitionbetween the extended configuration and the compressed configuration dueto changes in intraluminal pressure.
 13. The valve of claim 12, whereinthe biasing member is a spring.